A passerby saw flames and called the fire department, however when crews arrived the flames were so strong firefighters could not get into the home.

Sources told NewsCenter 5 the victims were Ronald Jones, 89, and his wife, Margaret, who was in her 80s.

The couple was found in the rubble, fire officials said. The victims were found in the basement, but they may have fallen there when the home collapsed, officials said.

"Given the time of day, it was appropriate to consider that there possibility that there would be people in the building. We attempted to make entry, but we were driven back," Concord Fire Department Chief Mark Cotreau said.

Neighbors said the couple has lived in the home for years.

Fire Marshall Stephen Coan says investigators think they know the area where the fire may have started, but have "no point of origin."

It was not immediately clear if the home had working smoke detectors, but responding firefighters did not report hearing any.

The couple's deaths bring the total number of people killed in Massachusetts fires this year to eight. Coan said most were "related to winter weather" in some way.

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